I'm looking into fortify issues identified in some open source C code our service uses and see code like this;
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} else if (n < (1024LL*1024*1024)) {
..
What is the significance of the LL on 1024LL as opposed to just 1024? Thanks.
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[This literal suffix table](https://en.cppreference.com/w/c/language/integer_constant#The_type_of_the_integer_constant) could be useful. – Some programmer dude Jan 04 '19 at 18:00
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LL is a suffix that means long long. In that particular snippet of code, the writer is saying one of the terms is 1024 but stored in a long long way. C has a rule that says the largest bits of any of the terms will be what it uses when it resolves integer math. Without the LL, then, 1024 * 1024 * 1024 would just overflow.
TJ Bandrowsky
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"C has a rule that says the largest bits of any of the terms will be what it uses when it resolves integer math" --> Yes (use highest rank) for 2 terms, no for 3 terms as all are done 2 terms at a time. – chux - Reinstate Monica Jan 04 '19 at 19:14
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`1024 * 1024 * 1024` would not overflow 32-bit `int`. Still `1024LL*1024*1024` is a good [idea](https://stackoverflow.com/a/40637622/2410359). – chux - Reinstate Monica Jan 04 '19 at 19:15